Mining and drilling Volume I:

In recent years, interest in mine workings has grown considerably in the mining industry, as it has in all professional mining practices. We have chosen to add this clarification, in the form of a postscript, to this chapter devoted to mining in general. Proposed mining projects vary according to the type of metals or materials to be extracted from the earth. The majority of proposed mining projects concern the extraction of ores such as: Copper, Nickel, Cobalt, Gold, Silver, Lead, Zinc, Molybdenum and Platinum.